The regulatory use of the Local Lymph Node Assay for the notification of new chemicals in Europe

The regulatory use of the Local Lymph Node Assay (LLNA) for new chemicals registration was monitored by screening the New Chemicals Database (NCD), which was managed by the former European Chemicals Bureau (ECB) at the European Commission Joint Research Centre (JRC). The NCD centralised information for chemicals notified after 1981, where toxicological information has been generated predominantly according to approved test methods. The database was searched to extract notifications for which the information for skin sensitisation labelling was based on results derived with the LLNA. The details of these records were extracted and pooled, and evaluated with regard to the extent of use of the LLNA over time, as well as for analysing the information retrieved on critical aspects of the procedure e.g. strain and amount of animals used, lymph node processing, solvent and doses selected, stimulation indices, and for assessing their level of compliance to the OECD Test Guideline 429. In addition the accuracy of the reduced LLNA when applied to new chemicals was investigated.

► We have monitored the regulatory use of the LLNA for new chemicals registration in Europe. ► We found 673 notifications that reported LLNA results and extracted the information. ► We analysed the information for different aspects of the LLNA procedure. ► We analysed the performance of a reduced version of the LLNA in this database. ► The accuracy of the reduced LLNA was above 98% compared to the classical version of the LLNA.